Winter Driving: It’s All About the Tires

Overnight, we had yet another snowstorm in the Mid-Atlantic region. When I woke up this morning, I looked outside and saw that heavy winds had blown most of the snow off of my driveway and the 2010 Infiniti FX50 Sport that I’m reviewing this week. The office opened on time this morning, so I decided to venture out into the unknown for the 26 mile drive to work. Knowing that I had a fallback – remote access – if conditions turned out to be too poor, there was no pressure on me to make it the whole way into the office.

But alas, I had a trump card. The kind folks who delivered the FX50 to me earlier in the week slapped a set of low-profile Bridgestone Blizzak snow tires onto its 21 inch rims. It’s always comforting to receive a car during the winter – particularly when snow is expected – that has the appropriate tires mounted to it. When I took an Acura TL SH-AWD 6MT on a several hundred mile road trip last month that included considerable portions of bad weather, it was not equipped with snow tires. In fact, it didn’t have all-seasons – it had summer tires. That’s not far from the notion of wearing flip-flops to shovel snow.

It looks like this today, except the snow is white instead of dark brown.

The FX50 Sport that I have this week (review coming soon, by the way) originally came with 265/45ZR21 Dunlop SP Sport 01 summer high performance tires. Those tires are going for $289.00 each at tirerack.com. The Bridgestone Blizzak DM-Z3 light truck snow tires that are installed on the FX50 today are on sale for $249.00 each at tirerack.com (regularly $287.00 each). So, how much does a set of good snow tires improve a vehicle’s acceleration, handling, and braking in wintry conditions for the $1,000 (not including installation and balancing) that a set of Blizzaks would set you back? Dramatically.

While this is not exactly an apples-to-apples comparison (since I didn’t have a spare FX50 on hand this morning equipped with summer or all-season tires), I can share some general winter driving observations of the FX50 AWD with snow tires, a Lincoln MKS EcoBoost with all-seasons, and the aforementioned Acura TL SH-AWD 6MT with summer tires. At one point over the past several months, I drove each of these three vehicles in similar conditions, and all are 300-plus horsepower performance-oriented vehicles. Their all-wheel drive systems are designed differently, but as the title says, I believe the tires make the biggest difference.

Summer Tires and AWD
As mentioned above, the Acura TL had summer tires (specifically, 245/40ZR19 Michelin Pilot Sport PS2). When I set off driving the TL for the first time, I was aware that it was all wheel drive, but not aware that it had summer tires. The TL’s all wheel drive was able to compensate somewhat for the inappropriate rubber, but the summer tires were particularly noticeable during braking. In spite of having ABS, I skidded past my expected stop point on a number of occasions on snowy and slushy roads. The TL’s manual transaxle allowed me to carefully modulate acceleration (and to start driving in second gear when necessary), so I found acceleration to be tolerable in snow. However, without careful throttle application, the car tended to jump laterally from time to time until the throttle was more moderately applied or until the tires were able to find a less-slippery surface to grab onto.

All-Season Tires and AWD
The Lincoln MKS EcoBoost that I drove a few weeks ago was equipped with all wheel drive and 245/45R20 Michelin Primacy MXV4 Grand Touring All-Season tires. Unlike the Acura, of course, the MKS is equipped with an automatic transaxle and has around 50 more horsepower that it has to get to the ground. While my time driving the Lincoln on snow-covered roads was more limited, one day, in an attempt to navigate away from main-road traffic, I detoured onto some side streets. Unfortunately, those streets were not plowed. The MKS did all right, though. I was even facing uphill and stopped at a traffic light, sitting on top of a few inches of snow, and the MKS managed to get moving despite the uphill challenges of snow and the hill. The MKS’ fairly considerable weight probably helped in this regard.

On another day, I had the MKS on a street with about three inches of slush and snow, and had to impatiently wait while a front wheel drive car was slipping and sliding in a fruitless attempt to pull into a parking space at the post office. Eventually, the driver of that car left enough room for me to get around her, and I hit the gas, drove around her, and cleanly backed into a parking space with no wheelspin or drama, all while the other driver had barely moved another foot. Too bad the snow had forced the post office to close that day and it was a wasted trip. The car felt reasonably stable on all-season tires, but if I lived in a climate that had more frequent snowfall (and people who live in those areas know who they are), I’d prefer additional security that more appropriate tires bring to the table.

Snow Tires and AWD
When I received the Infiniti FX50 Sport for evaluation, one of the first things I did was inspect the tires, since I knew that snowfall was in the forecast. Bridgestone Blizzaks are likely the best-known snow tire brand sold in the US. At least they’re the first one that comes to mind when I think of snow tire brands, and happen to be the only ones available at the Tire Rack in the FX50’s OEM size.

I backed out of my driveway into a sizable snow drift, and the FX didn’t slip an inch. I gently made my way to the end of the street, and slipped only a foot or two at the stop sign. I made my way onto the main road, and for the rest of a 25 mile drive through mostly back roads, including some city travel with traffic lights, I don’t think the big FX slipped again once. I set it to “snow” mode prior to departing, which dulls throttle responses (finally – a benefit of the much-maligned drive-by-wire throttle!) and drove at a moderate pace, keeping a safe following distance and dodging drifted snow whenever possible. Thinking back to my time in the Acura with summer tires, stopping distances were dramatically improved in the FX50 with the Blizzaks.

Interestingly, the Tire Rack does not seem to recommend installing 21 inch diameter snow tires on the FX50. I had to search for that specific tire size to get its listing page; instead, they recommend purchasing an 18 inch tire and wheel package for the winter tires only. This is actually a very good strategy; you get winter driving safety and protect your expensive aluminum rims from hidden curb and pothole damage, and keep the road salt far away from them. It also allows you to change from summer to winter tires yourself without needing to go to the local tire shop for a dismount, remount, and rebalance twice a year. That saves time and money.

The Tire Rack’s recommended 265/60R18 Bridgestone Blizzak DM-V1 snow tires are $146 each, and the site’s cheapest 18×8 inch aluminum rims (steelies apparently aren’t available in the 18 inch size) are $129 each. All told, that is $1,100 for tires and rims, not including $129.65 in shipping, sales tax, installation, and TPMS sensors. If you want to take advantage of the Infiniti’s tire pressure monitoring system (TPMS), it’s another $396. I’d probably go for the 18 inch wheel and tire package, probably skip the TPMS, and keep the pristine condition of my stock 21 inch wheels and tires. Then I’d just need a floor jack to swap the summer for winter tires each year, and vice versa.

Spending this morning driving through snow and all wheel drive gives me sufficient confidence that I could safely take my family on a road trip in the FX50 this weekend to visit relatives, and I don’t think I’d have the same comfort level with all-season tires, even with all wheel drive. Truly, it’s all about the tires.

Chris is Autosavant's Managing Editor. He has a lifelong love of everything automotive, having grown up as the son of a car dealer. A married father of two sons, Chris is also in the process of indoctrinating them into the world of cars and trucks.